Metalliferous azo-dyestuffs



United States Patent 3,005,813 METALLIFEROUS AZO-DYESTUFFS JakobBrassel, Basel, and Arthur Buehler, Rheinfelden, giwizcrland, assignorsto Ciba Limited, Basel, Switzeran No Drawing. Filed May 20, 1954, Ser.No. 431,270 Claims priority, application Switzerland May 22, 1953 2Claims. (Cl. 260145) This invention provides a process for the manufacture of valuable new metalliferous azo-dyestulfs, which contain one atomof metal in complex union with two molecules of difierentmonoazo-dyestufls, wherein a mix ture of two different metallizablemonoazo-dyestufis, of which one contains a single free sulfonic acidgroup and the other is free from sulfonic acid and carboxylic acidgroups, and at least one of which dyestuffs, advantageously the dyestufifree from sulfonic acid and carboxylic acid groups, contains a sulfonicacid aryl ester group or advantageously a sulfone group or a sulfonicacid amide group, is treated with an agent yielding cobalt oradvantageously chromium under conditions such that the resultingmetalliferous azo-dyestuft contains, per molecular proportion ofmonoazo-dyestuff, less than one, but at least one half, atomicproportion of cobalt or chromium bound in complex union.

The monoazo-dyestufis containing a single sulfonic acid group, and usedas starting materials in the present process, may be ortho carboxy orthohydroxy-, ortho:ortho'-dihydroxyor orthohydroxyorthd-arninomonoazo-dyestuifs. They can be obtained by couplingan ortho-carboxyor an ortho-hydroXy-diazo compound, advantageously oneof the benzene or naphthalene series, with a coupling component capableof coupling in orthoposition to a hydroxyl or amino group, thecouplingcomponent or advantageously the diaZo-component containing asingle sulfonic acid group.

As diam-compounds there are advantageously used diazo compounds of thoseortho-hydroXy-amines of the benzene or naphthalene series which, inaddition to the hydroxyl and amino group, contain further substituentsincapable of salt formation, such as nitro groups, halogen atoms (forexample, chlorine), alkyl groups (for example, methyl), alkoxy groups(for example, CH -O--), acylamino groups, especially those containingonly a few carbon atoms, that is to say, at most 4 carbon atoms (forexample, acetylamino), or a sulfonic acid amide group which isadvantageously substituted.

As examples there may be mentioned:

(a) Amines free from sulfonic acid groups 4- orS-chloro-Z-amino-l-hydroxybenzene,

4-, 5- or 6-nitro-2-amino-l-hydroxybenzene,

4 6-dichloro-2-arnino4-hydroxybenzene,

3 :4 6-trichloro-2-amino-1-hydroxybenzene,

4-chloro-5- or -6-nitro-2-amino-1-hydroxy benzene,

4-nitro-6-chloro 2-amino-l-hydroxybenzene,

4-nitro-6-acetylamino-2-amino-l-hydroxybenzene,

6-nitro-4-acetylamino-2-amino-l-hydroxybenzene,

4 6-dinitro-2-amino- 1 -hydroxybenzene,

l-amino-2-hydroxynaphthalene,

Z-amino-l-hydroxybenzene-4- or -5-sulfonic acid phenylamide,

4 chloro 2 amino-l-hydroxybenzene-S-sulfonic acid phenylorN-ethyl-N-phenylamide,

Z-amino-l-carboxylic acid, and especially (b) Amines containing one --SOI-I group Z-amino-benzene-l-carboxy lic acid-4- or -5-su1fonic acid,2-amino-1-hydroxybenzene-4- or -5-su1fonic acid,

4-chloro or 4-methyl-2-amino-l-hydroxybenzene-S- or -6- sulfonic acid,4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid,6-nitro-2-amino-l-hydroxybenzene 4 sulfonic acid and above allnaphthalene compounds, such as Z-amino-1-hydroXynaphthalene-4- or-8-sulfonic acid, 6-nitro-1-amino-2-hydroxynaphthalene-4-sulfonic acid,6-bromoor 6-methoxy-l-amino-2-hydroXynaphthalene-4- sulfonic acid andespecially 1-amino-2-hydroxynaphthalene-4-su1fonic acid.

As coupling components there come into consideration those which arecapable of coupling in a position vicinal to a primary-or secondaryamino group or a hydroxyl group, and among these there are also includedketo-compounds which are capable of coupling in a position vicinal totheir enolized or enolizable keto group.

As examples of suitable coupling components there may be mentioned:

(a) Coupling components free from sulfonic acid groups Hydroxybenzenes,such as para-cres-ol or para-tertiary amylphenol, fi-keto-carbaxylicacid esters or amides, such as aceto-acetic acid anilide andl-acetoacetylamino-2-, -3- or -4-chlorobenzene; pyrazolones such as1-phenyl-3- methyl-5-pyrazolone, 1-(2'-ethyl-phenyl) 3 methyl-S-pyrazolone, l:3-diphenyl-5-pyrazolone, 1-(2-, 3- or 4'- chlorophenyl) -3-methyl-5-pyrazolone, 1-(2.' 5'-dichlorophenyl)-3-methyl-5-pyrazolone,1-(2'-, 3'- or 4-methyl phenyl)-3-methyl 5 pyrazolone, 1- [naphthyl-(l)-or -(2')]-3-methyl-5-pyrazolone, l-phenyl 5 'pyrazolone- 3 carboxylicacid phenylamide, 1-n-octyl-3-methy1-5- pyrazolone; hydroxyquinolines;barbituric acids; and especially naphthylamines or naphthols such as6-bromo-, 6-methoxyor 6-methyl-2-arninonaphthalene,Z-phenylaminonaphthalene, Z-aminonapht-halene itself and2-aminonaphthalene-l-sulfonic acid which is known to couple to form thesame dyestuffs as Z-aminonaphthalene accompanied by the splitting oil ofthe SO H group in the 1-position, and also 6-bromo-, 6-methyl or6-metl1- oXy-2-hydroxynaphthalene and especially l-acetylamino-7-hydroxynaphthalene, l-n-butyrylamino 7 hydroxynaphthalene,1-benzoylamino-7-hydroxynaphthalene, -1- carbethoxyamino 7hydroxynaphthalene, 8-chloro-lhydro rynaphthalene, 5-chloro-1-hydroxynaphthalene, 5 8- dichloro-l-hydroxynaphthalene, 4:8-or 5 8-dichloro-2-hy-. droxynaphthalene, Z-hydroxynaphthalene and, ifdesired, l-hydroxynaphthalene. These compounds must be coupled only withdiam-compounds of the amines mentioned under (b) above.

(b) Coupling components containing one -SO H groupl-phegyl-S-methyl-5-pyrazolone-2-, -3- or -4'-sulionic aci 2'-chloro 1phenyl-3-methyl-5-pyrazolone-4'- or 5'-su1- fonic acid,

2':5-dichloro l phenyl-B-methyl5-pyrazolone-4-sulfonic acid,

1-[naphthyl-(1)] 3 methyl 5 pyrazolone-4'-, -5'-,

-6'-, -7'- or -8'-sulfonic acid,

1- [naphthyl-(2)] 3 methyl 5 pyrazolone-2'-, or -8- sulfonic acid,

1-acetoacetylaminobenzene-4-sulfonic acid and above all Y Z-aminoor2-hydroxynaphthalene-4-, -5-, -6- or -7-sulfonic acid,1-hydroxynaphtha1ene-4-, -5- or -8-sulfonic acid,2-phenylaminonaphthalene-3- or -4'-sulfonie acid.

These coupling components must be coupled only with diazo compounds ofamines free from sulfonic acid groups as mentioned under (a) above.

The monoazo-dyestufis free from sulfonic acid and carboxylic acidgroups, which are also used as starting materials in the presentprocess, can be made, for example, by coupling anortho-hydroxy-diazo-compound of the benzene or naphthalene series with acompound capable of coupling in a position vi'cinal to an amino orhydroxyl group or an .enolizable keto group, and the starting materialsare advantageously so chosen. that at least one of them contains aconverted sulfonic acid group, that is to say, a sulfonic acid arylester group, and especially a sulfone group or a sulfonic acid amidegroup. Those dyestuffs which contain such a converted sulfonic acidgroup are used as starting materials only when the dyestutf containing asingle free sulfonic acid group is free from sulfone groups and sulfonicacid amide groups.

As ortho-hydroxy-diazo-compounds for preparing the dyestufis free fromsulfonic acid and carboxylic acid groups there came into consideration,for example, those mentioned above under (a) in connection with thepreparation of the monoazo-dyestufis containing a sulfonic acid group.Especially valuable starting materials are obtained, however, withdiam-compounds of amines containing a sulfone group or a sulfonic acidamide group, such as 4-chloroor 4-nitro-2-amino-l-hydroxybenzene-6-sulfonic acid amide, 6-nitro-2-amino-l-hydroxybenzene- 4-sulfonic acidamide, 2-amino-1-hydroxybenzene-4- or --sulfonic acid met-hylamide,Z-arnino-l-hydroxybenzene- 4- or -5-sulfonic acid phenylamide,Z-amino-l-hydroxybenzene-4- or -5-sulfonic acid dimethylamide,4-chloro-2- amino 1 hydroxybenzene-S-sulfonic acid methylamide,ethylamide, isopropylamide or phenylamide, 4-chloro-2-amino-1-hydroxybenzene-5-sulfonic acid dimethyl amide, diethylamide orN-methyl-N-phenylamide, and the corresponding compounds which contain,instead of a sulfonic acid amide group, a methyl sulfone group, an ethylsulfone group or especially a phenyl sulfone group, a paramethylorpara-chloro-phenyl sulfone group.

As coupling components for preparing the monoazodyestutfs free fromsulfonic acid and carboxylic acid groups there may be mentioned:

The coupling components free from sulfonic acid groups mentioned above,and also l-phenyl-S-methyl-S- pyrazolone-3'-sulfonic acid amide,1-phenyl-3-met-hyl-5- pyrazolone-3-sulfonic acid methylamide,2:4-dihydroxyquinoline, S-chloro-8-hydroxyquinoline, and 2aminonaphthalene-4-, -5- or -6-sulfonic acid amides, and amides orphenyl esters of 1-hydroxynaphthalene-4-, -5- or -8- sulfonic acid or of2-hydroxynaphthalene-4-, -6- or -7- sulfonic acid.

For preparing both kinds of starting materials coupling of thediazo-compounds is carried out by methods in themselves known in anacid, neutral or alkaline medium. When amino-compounds are used ascoupling components the coupling is advantageously carried out in anacid to neutral medium.

The mixture of the two dyestufls to be metallized can be obtained, notonly by mixing together the individual dyestufis, but for example, bycoupling 2 mols of one of the above mentionedortho-hydroxy-diazo-compounds, which is free from sulfonic acid groups,with one mol each of two difierent coupling components of which onecontains a sulfonic acid group and the other contains as a substituent asulfone radical or a sulfonic acid amide radical. Furthermore, forexample, 2 mols of a coupling component free from sulfonic acid groupsmay be coupled with 1 mol each of two different, advantageouslyselected, diazo-compounds. Especially valuable results are obtained with'rnixtures of the aforesaid monazo-dyestuifs, which contain at least onemole of the monoazodyestuff free from sulfonic acid and 'carboxylic acidgroups per mol of a monoazo-dyestuff containing one free sulfonic acidgroup.

' As agent-s yielding metal there are used in the present process agentsyielding cobalt, or more especially agents yielding chromium.

In carrying out the process it is generally of advantage to use aquantity of the agent yielding metal corresponding to about one atomicproportion of metal for each molecular proportion of the two differentdyestuffs present in the mixture and/or to carry out the metallizationin a Weakly acid to alkaline medium. Accordingly, there are especiallysuitable for carrying out the process agents yielding metal which arestable in alkaline media, such, for example, as cobalt compounds ofaliphatic hydroxycarboxylic acids or dicarboxylic acids andadvantageously chromium compounds of aromatic ortho-hydroxy-carboxylicacids, which contain the metal in complex union. As examples ofaliphatic hydroxy-carboxylic acids there may be mentioned, inter alia,lactic acid, citric acid and especially tartaric acid, and as adicarboxylic acid there may be mentioned oxalic acid, and among thearomatic hydroxy-carboxylic acids there may be mentioned those of thebenzene series such as 4-, 5- or 6-methyl-1-hydroxybenzene-Z-carboxylicacid and above all l-hydroxybenzene-Z-carboxylic acid itself. As agentsyielding cobalt, however, it is of advantage to use simple cobalt salts,such as cobalt sulfate, or if desired, freshly precipitated cobalthydroxide.

Conversion of the dyestuifs into their complex metal compounds isadvantageously carried out at a raised temperature, under atmospheric orsuperatmospher-ic pressure for example at the boiling temperature of thereaction mixture, if desired, in the presence of a suitable addition,for example, salts of organic acids, bases, organic solvents or otheragents assisting the formation of complexes. When an excess of thedyestuff containing a sulfonic acid group is used, it is possible by thesubsequent addition of fresh quantities of the dyestuif free fromsulfonic acid and carboxylic acid groups and, if desired, by theaddition of the alkaline metallizing solution, to complete themetallization without forming appreciable quantities of the lzl-complexof the dyestuff containing a sulfonic acid group.

The metal compounds obtainable by the process described above can alsobe obtained by a modification of that process, in which a metal-freemonoazo-dyestuff and a metalliferous monazo-dyestuff, which containsabout one atom of chromium or cobalt bound in complex union per moleculeof dyestuff, are reacted together, and the two monoazo-dyestuffs are sochosen that one of them contains a free sulfonic acid group and theother contains no free sulfonic acid or carboxylic acid groups, and thatat least one of these dyestuffs, advantageously the monoaZo-dyestuiffree from sulfonic acid and carboxylic acid groups, contains a sulfonicacid aryl ester group or especially a sulfone group or a sulfonic acidamide group.

The metal compounds of monoazo-dyestulfs used as starting materials inthe latter :form of the process, and which contain one atom of chromiumor cobalt bound in complex union per molecule of dyestuff, are so-calledlzl-complexes which can be made by methods in themselves known, forexample, by reacting the monoazodyestutf free from complex-formingmetal, advantageously the dyestufi which contains a sulfonic acid group,in an acid medium with an excess of a salt of the said metal, forexample, a cobalt salt or advantageously a salt of trivalent chromium,such as chromium sulfate or chromium fluoride at the boiling temperatureor, if desired, at a temperature exceeding C. When, instead of theorthozorthd-dihydroxyor ortho-hydroxy-orthoamino-monoazo-dyest-ufls ofthe kind defined above there are used the correspondingortho-alkoxy-ortho'-hydroxyorortho-alkoxy-ortho'-amino-monoazo-dyestuffs, the latter are subjected toa de-alkylating metallization, and there are obtained the same1:1-complexes used as starting materials in the modified process. Inorder to convert the metal-free dyestuffs tree from sulfonic acid groupsinto the lzl-complexes it is generally of advantage to carry out themetallization in the presence of an organic solvent, for example,alcohol.

The reaction of the 1:1-metal complexes so obtained with the metal-freedyestuflfs is advantageously carried out in an aqueous neutral to weaklyalkaline medium'at the ordinary'temperature or a raised temperature. Itis generally desirable to react together approximately equivalentquantities of the metalliferous lzl-complex and the metal-free dyestufi.

The new products obtainable by the processes described above are metalcompounds which contain one atom of chromium or cobalt bound in complexunion with two molecules of different monoazo-dyestufis, of which onecontains a single free snlfonic acid group and the other contains nofree sulfonic acid or carboxylic acid groups, and of which at least one,advantageously the dyestufl free from sulfonic acid and carboxylic acidgroups, contains a sulfonic acid aryl ester group or more especially asulfone group or sulfonic acid amide group.

Mixtures of such metalliferous mixed complexes can be obtained by theprocesses described above by reacting an agent yielding metal of theaforesaid kind simultanea ously with two or more dyestuitmixtures of thekind defined above or by reacting a metalliferous lzl-complexsimultaneously with two or more metal-free-dyestufis or two or moremetalliferous lzl-complexes with a metalfree dyestuff in suitablerelative proportions. Especially valuable are those mixtures of mixedcomplexes in which the number of mols of the dyestufi containing asulfonic acid group is at most equal to that of the dyestufi free fromsulfonic acid and carboxylic acid groups.

The new metalliferous mixed complexes obtainable by the process of thisinvention are soluble in water. They are suitable for dyeing or printinga very wide variety of materials, but especially for dyeing animalmaterials such as silk, leather and especially wool (including loosewool), and also for dyeing or printing synthetic fibers ofsuperpolyamides, superpolyurethanes or polyacrylonitrile. They areespecially suitable for dyeing from weakly alkaline, neutral or weaklyacid baths, advantageously acetic acid baths. The dyeings so producedare level and possess a good fastness to light, washing, fulling,decatizing and carbonizing.

The following examples illustrate the invention, the percentages beingby weight, and 1 mol means, as is usual, the molecular weight of thesubstance in grams but the quantities given may of course be increased,for example, to or 1000times the values given. When the dyestufis usedas starting materials are not in a pure form, for example, in the formof closely defined dyestufi acids or dyestuff salts, but contain, forexample, as the result of being precipitated by salting out, foreignsubstances which have substantially no adverse effect on the reaction,such dyestutfs can normally be used in that form with good success'.However, it is then necessary to determine the content of pure dyestuifby any known method, for example, by titration of the azo groups:

EXAMPLE 1 0.01 mol of the dyestuii from diazotized 1-amino-2-hydroxynaphthalene-4-sulfonic acid and 2-hydroxynaph thalene is boiledunder reflux forone hour with 0.01 mol of the dyestuif from diazotized4-chloro-2-arnino-1-hydroxybenzene-S-sulfonic acid methylamide andZ-hydroxynaphthalene in 400 cc. of water with the addition of 2 cc. of a10 N-solution of sodium hydroxide and 30 grams of a solution of sodiumchromosalicylate having a chromium content of 2.6 percent. It required,the mixture is filtered to remove a small amount of impurities. Thechromium complex so formed is'precipitated from its solution by theaddition of 60 grams of sodium chloride, filtered 0E and dried. Theresulting water-soluble chromiferous dyestufi dyes wool from neutral toacetic acid baths level blue tints which are fast to washing, fullingandlight.

EXAMPLE 2 0.01 mol of the dyestufi from diazotized l-amino-Z-hydroxynaphthalene-4-sulfonic acid and 8-chloro-l-hydroxynaphthalene isboiled under reflux for one hour with 0.01 mol of the dyestufi fromdiazotized Z-amino-l-hydroxybenzene-S-sulfonic acid amide and5:8-dichloro-lhydroxynaphthalene in 400 cc. of water with the additionof 2 cc. of a 10 N-solution of sodium hydroxide and 30 grams of asolution of sodium chromosalicylate having a chromium content of 2.6percent. If required, the mixture is filtered to remove a small amountof impurities. The chromium'co'rnplex so formed is precipitated from itssolution by the addition of grams of sodium chloride and 9 cc. of 2N-acetic acid, filtered oil and dried. The chromiferous dyestuff soobtained dyes Wool from neutral or acetic acid baths level blue tintswhich are fast to washing, fulling and light.

EXAMPLE 3 0.009 mol of the dyestuit from diazotized l-amino-2-hydroxynaphthalene-4-sulfonic acid and 5:8-dichloro-1-hydroxynaphthalene are boiled under reflux for one hour with 0.01 mol ofthe dyestufi from diazotized 2-amin0- 1-hydroxybenzene-S-Sulfonic acidamide and 5 :S-dichlorol-hydroxynaphthalene in 400 cc. of Water with theaddition of 2 cc. of a 2 N-solution of sodium hydroxide and 30 grams ofa solution of sodium chromosalicylate having a chromium content of 2.6percent. If required, the mixture is filtered to remove a small amountof impurities. The chromiferous dyestufl so obtained is precipitatedfrom solution by the addition of grams of sodium chloride and 8 cc. of 2N-acetic acid, filtered off and dried. It dyes Wool from neutral oracetic acid baths level blue tints which are fast to washing, fullingand light.

By using, instead of 0.009 mol of the dyestuir" from diazotized1-amino-2-hydroxynaphthalene-4-sulfonic acid and5:8-dichioro-1hydroxynaphthalene, 0.011 mol of the dyestuif fromdiazotized 1-amino-2-hydroxynaphthalene 4-sulfonic acid andl-hydroxynaphthalene there is obtained a dyestuff having similarproperties.

EXAMPLE 4 0.01 mol of the dyestuif from diazotized2-amino-lhydroxynaphthalene-8-sulfonic acid and5:8-dichloro-lhydroxynaphthalene is boiled under reflux for3 hours with0.01 mol of the dyestuff from diazotizedZ-amino-lhydroxybenzene-4-sulfonicacid amide and 5:8-dichloro-1-hydroxynaphthalene in 400 cc. of Water with the addition of 2 cc. of a10 N-solution of sodium hydroxide and 30 'grams of a solution of sodiumchromosalicylate having a chromium content of 2.6 percent. The reactionmixture is allowed to cool and filtered to remove a small amount ofimpurities. The chromium complex so formed is precipitated fromsolution'by the addition of 50 grams of sodium chloride and 4Icc. of 2N-acetic acid, filtered off and dried. It dyes wool from neutral oracetic acid baths level blue tints which are fast to wrshingQfulling andlight.

EXAMPLE 5 0.01 mol of the dyestuif from diazotized 4-nitro-2-amino-1-hydroxybenzene-6-sulfonic acid and -methoxy-2-hydroxynaphthalene is boiled under reflux for one hour with 0.01 molof the dyestuff from diazotized Z-amino-lhydroxybenzene-S-sulfonic acidamide and 5z8-dichlorol-hydroxynaphthalene in 400 cc. of water with theaddition of 10 cc. of a 2 N-solution of sodium hydroxide and 30 grams ofa solution of sodium chromosalicylate having a chromium content of 2.6percent. If required, the mixture is filtered to remove a small amountof impurities. The chromium complex so formed is precipitated fromsolution by the addition of grams of sodium chloride and 12 cc. of 2N-acetic acid, filtered off and dried. It

7 dyes wool from neutral or acetic acid baths level bluegrey tints whichare fast to washing, fulling and light.

A similar chromium compound is obtained by using, instead of the6-methoxy-2-hydroxynaphthalene, an equivalent quantity of:8dichlor0-l-hydroxynaphthalene.

EXAMPLE 6 0.006 mol of the dyestuff from diazotized 1-amino-2-hydroxynaphthalene-4-sulfonic acid and 2-hydroxynaphthalene are boiledunder reflux for one hour with 0.004 mol of the dyestuff from diazotizedl-amino-Z-hydroxynaphthalene-4-sulfonic acid and5:8-dichloro-1-hydroxynaphthalene and with 0.01 mol of the dyestuff fromdiazotized 4-chloro-2-arnino-l-hydroxybenzene 5 sulfonic acidmethylamide and 2-hydroxynaphthalene in 400 cc. of water with theaddition of 2 cc. of a N-solution of so dium hydroxide and 30 grams of asolution of sodium chromosalicylate having a chromium content of 2.6percent. If required, the mixture is filtered to remove a small amountof impurities. The chromiferous dyestufi is precipitated from solutionby the addition of 60 grams of sodium chloride, filtered off and dried.It dyes wool from neutral or acetic acid baths level blue tints whichare fast to washing, fulling and light.

EXAMPLE 7 0.009 mol of the dyestuff from diazotized l-amino-Z-hydroxynaphthalene-4-sulfonic acid and 5:8-dichloro-lhydroxynaphthaleneare boiled under reflux for one hour with 0.005 mol of the dyestuif fromdiazotized Z-amino-lhydroxybenzene-4-sulfonic acid methylamide and2-hydroxynaphthalene and with 0.005 mol of the dyestuff from diazotized4 chloro 2 amino 1 hydroxybenzene-S- sulfonic acid methylamide and2-hydroxynaphthalene in 400 cc. of water with the addition of 2 cc. of a10 N-solution of sodium hydroxide and 30 grams of a solution of sodiumchromosalicylate having a chromium content of 2.6 percent. If required,the mixture is filtered to remove a small amount of impurities. Theresulting chromiferous dyestufi is precipitated from solution by theaddition of 60 grams of sodium chloride, filtered off and dried. It dyeswool from neutral or acetic acid baths level blue tints which are fastto washing, fulling and light.

EXAMPLE 8 0.01 mol of the dyestuff from nitrated1-diazo-2-hydroxyna-phthalene-4-sulfonic acid and Z-hydroxynaphthaleneis boiled under reflux for 2 hours with 0.01 mol of the dyestuif fromdiazotized 2-amino-l-hydroxybenzene- 4-sulfonic acid methylamide andZ-hydroxynaphthalene in 400 cc. of water with the addition of 10 cc. ofa 2 N- solution of sodium hydroxide and 30 grams of a solution of sodiumchromosalicylate having a chromium content of 2.6 percent. It required,the mixture is filtered to remove a small amount of impurities. Thechromiterous dyestuff is precipitated from solution by the addition of80 grams of sodium chloride, filtered oil and dried. It dyes wool fromneutral or acetic acid baths level violet-brown tints which are fast towashing, fulling and light.

EXAMPLE 9 0.01 mol of the complex chromium compound (containing onemolecule of dyestuif bound in complex union with one atom of chromium)of the dyestufi from diazotized l-arnino-2-hydroxynaphthalene-4-sulfonicacid and 2-hydroxynaphthalene is 'boiled under reflux for 30 minuteswith 0.01 mol of the dyestuif from diazotized 4-chloro-Z-amino-1-hydroxybenzene-5-sulfonic acid methylamide andZ-hydroxynaphthalene in 400 cc. of water with the addition of 2 cc. of a10 Nasolution of sodium hydroxide. If required, the mixture is filteredto remove a small mount of impurities. The chromium complex so formed isprecipitated from solution by the addition of 60 grams of sodiumchloride, filtered otf and dried. The

resulting water-soluble rchromiferous dyestufi possesses the same dyeingproperties as the dyest-ufif of Example 1,.

By using, instead of the complex chromium compound and metal-freevdyestufif mentioned in this example, those given in columns I and II,respectively, of the following table, there are obtained mixed chromiumcomplexes which dye wool from weakly acid baths the tints given incolumn HI:

I II III 1:1-e0rnplex chromium chromium-free tint compound dyestufi 14-nltro-2-amln0- 2-amlno-phenol-4- orange. phcnol-fifsulionlcphenyl-sulionefl acid+1-phenyl-3- aoetoacetlc acidmethyl-,fi-pyrazoanllide. lone.

2 l-arnino-Z-hydroiry-G- z-eminophenolfste grey.

nitro-naphthalene-4- methyl-sulfone-d, sultonic acid-q8-carbo-methoxynaphthol. amino-7-hydroxynaphthalene.

3 4-nitro-2-arnino- 4-chloro-2-arnino red brown? phcnol-fisulionlcphenol- 2-hydroxyacid- 1-phenyl-3- naphthalene-6-methyl-.S-pyrazosulfonic acid phenyl lone. ester.

4 Z-amlnobcnzoic acid- 2-amlnophenol-4- grey.

1-phenyl-3-methylsuliarnide-r5r8- 6-pyraz0lone-4- dichloro-l-naphthol.sulionic acid.

5 do .Q 2-aminophenol-5- do.

' sulfamide-v5z8- dlchloro-l-naphthol.

phenol-S-sulfamide 4-tert. amyl-lhydroxybenzene.

7 fi-nitro-Z-arnino- 2-amlno-1-hydroxy: yellowish phenol-2-naphbenzene-i-sulionic olive. thylamino-Gsulacid isopropylamlde ionicacid. acetoacetic acid anlllde.

EXAMPLE 10 0.01 mol of the dyestuff from diazotized 5-nitr0-2amino-l-hydroxybenzene and 2-aminonaphthalene-6-sulionic acid is heatedat 75 C. with 0.01 mol of the dyestufl from diazotiged'2-aminoelehydroxybenzene-is ll' ionic acid is p cpy am de andacetoaceti aci anili e i 400 cc. of water with the addition of 12 cc. ofa 2 ,N-solu? tion of sodium' yd ide Af e he a d ion o a 50. tion of0.011 mol of cobalt acetate in 50 cc. of water, the reaction mixture isheated to 75 C. and then stirred for one hour at 75-80" C. If required,the mixture is filtered to remove a small amount of impurities. Thecobalt complex so formed is precipitated from solution by the additionof 70 grams of sodium chloride, filtered off d dr ed. The dyestufi s ota n dy 1 f om neutral baths green tints which are fast to Washing,falling and light.

EXAMPLE 11 2 Partsof t e hromirero s dy tufi ob a e as e scribed inExample 1 are'dissolved in 4000 parts of water, and parts of well wettedwool are entered at 49 50 C. into the resulting dyebath. 2. pints 9facetic acid of 40 percent strength are then added, the bath is raised tothe boil in the course of /2 hour and dyeing is continued at the boilfor hour. Finally, the wool is rinsed with cold water and dried. Thewool is dyed a navy bluetint of good fastnc s to light and washing.

- A navy blue dyeing is likewise obtained when no acetic acid is addedto the dyebath, or when, instead of wool, superpolyamide fibers (nylonfiberslare dyed in the marr ner described above.

What is claimed is:

1. A complex chromium compound containing one atom of chromium incomplex union with two molecules of two difierent ortho:ortho'-dihydroxymonoazo-dyestufis of which one corresponds to the formula OH H0 ('31wherein X represents a sulfonic acid amide group and Y represents amember of the group consisting of a chlorine and a hydrogen atom whilethe other mon'oazo-dyestufl corresponds to the formula wherein Rrepresents a member of the group consisting of al-hydroxy-S:S-dichloronaphthalene radical bound in 2-position to the azolinkage and a 6-methoxy-2-hydroxynaphthalene radical bound in l-positionto the azo linkage.

2. The complex chromium compound containing one atom of chromium boundin complex union with the monoazodyestnfis of the formulae (I)H HO I01HOQSON=N@ I NO: 01

and

OH H0 31 0213 NE: I

References Cited in the file of this patent UNITED STATES PATENTS1,984,096 Straub et a1 Dec. 11, 1934 2,012,779 Straub et a1 Aug. 27,1935 2,353,675 Knecht et al. "July 18, 1944 2,674,515 Widner et a1...Apr. 6, 1954 2,749,332 Buehler et al. -June 5, 1956

1. A COMPLEX CHLORIMUM COMPOUND CONTAINING ONE ATOM OF CHROMIUM INCOMPLEX UNION WITH TWO MOLECULES OF TWO DIFFERENTORTHO:ORTHO''-DIHYDROXY MONOAZO-DYESTUFFS OF WHICH ONE CORRESPONDS TOTHE FORMULA